Posted by **Mario Trujillo** on Tuesday, September 11, 2012 at 6:53pm.

1. A rectangular box has a square base, four sides, but no top. It has a volume of 20 cubic feet.

Let A be the surface area of the box, and L the length of one side of the base.

(a) The volume is measured in cubic feet. What units are convenient to use for the area A

and the side length L?

(b) Is A a function of L? If no, explain why not. If yes, nd the formula of A in terms of L

and point out its domain.